For a regular 15-gon:

The number of gallons of paint needed to cover a wall varies directly with the area of the wall. The Robertsons find that they u

Licemer1 [7]

Answer:

If 1/2 gallon covers 540 square feet, then 1 gallon will cover 1080 square feet.

Step-by-step explanation:

5 0

3 years ago

The scores on the GMAT entrance exam at an MBA program in the Central Valley of California are normally distributed with a mean

Kaylis [27]

Answer:

58.32% probability that a randomly selected application will report a GMAT score of less than 600

93.51% probability that a sample of 50 randomly selected applications will report an average GMAT score of less than 600

98.38% probability that a sample of 100 randomly selected applications will report an average GMAT score of less than 600

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal probability distribution

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

In this problem, we have that:

$\mu = 591, \sigma = 42$

What is the probability that a randomly selected application will report a GMAT score of less than 600?

This is the pvalue of Z when X = 600. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{600 - 591}{42}$

$Z = 0.21$

$Z = 0.21$ has a pvalue of 0.5832

58.32% probability that a randomly selected application will report a GMAT score of less than 600

What is the probability that a sample of 50 randomly selected applications will report an average GMAT score of less than 600?

Now we have $n = 50, s = \frac{42}{\sqrt{50}} = 5.94$

This is the pvalue of Z when X = 600. So

$Z = \frac{X - \mu}{s}$

$Z = \frac{600 - 591}{5.94}$

$Z = 1.515$

$Z = 1.515$ has a pvalue of 0.9351

93.51% probability that a sample of 50 randomly selected applications will report an average GMAT score of less than 600

What is the probability that a sample of 100 randomly selected applications will report an average GMAT score of less than 600?

Now we have $n = 50, s = \frac{42}{\sqrt{100}} = 4.2$

$Z = \frac{X - \mu}{s}$

$Z = \frac{600 - 591}{4.2}$

$Z = 2.14$

$Z = 2.14$ has a pvalue of 0.9838

98.38% probability that a sample of 100 randomly selected applications will report an average GMAT score of less than 600

8 0

3 years ago

What value of k makes the equation true? (5a^2 b^3)(6a^k b)=30a^6 b^4

Ratling [72]

we are given

$(5a^2 b^3)(6a^k b)=30a^6 b^4$

Firstly, we will simplify left side

and then we can solve for k

Left side is

$(5a^2 b^3)(6a^k b)$

we can arrange like terms

$(5a^2 6a^k)(b^3 b)$

$(5\times 6 a^2a^k)(b^3 b)$

$(30 a^2a^k)(b^3 b^1)$

now, we can use property of exponent

$a^m \times a^n=a^{m+n}$

$(30 a^{2+k})(b^{3+1})$

$30a^{2+k}b^{4}$

now, we can equate it with right side

and we get

$30a^{2+k}b^{4}=30a^6 b^4$

We can see that both sides have 30 , a and b

and they are equal

so, exponent of a must also be equal

$2+k=6$

now, we can solve for k

$2+k-2=6-2$

$k=4$ ................Answer

3 0

4 years ago

Read 2 more answers

Find the volume of the figure

Charra [1.4K]

8*10*14 = 1120
10*8*10 = 800
1120+800 = 1920
volume =1920 cm3

7 0

3 years ago

Travis owes Mickie $120. Each week he pays her $7. Which is an equation that describes the amount (A) that Travis owes after (W)

anyanavicka [17]

Answer:

120 - (W*7)= A

Step-by-step explanation:

Let's say after 3 weeks. $120 is what he owes her in the beginning. He pays her $7/week.

After 3 weeks, he owes her 120 - (W*7)= A.

W=3, since we are 3 weeks along. So, after 3 weeks he still owes her

120 - (3*7)= A >>> 120 - 21= A >>> 99= A.

5 0

3 years ago